With Gauff pouring on the pressure, Dodin began to crumble, piling up nine double faults and 26 unforced errors compared to just seven by her 20-year-old opponent.
Credit: Geoff Burke-USA TODAY Sports
Miami: It took Coco Gauff a while to wake up on Sunday, but when she did it was lights out for Oceane Dodin as the American third seed stormed back from 4-2 down to earn a 6-4 6-0 win and a place in the Miami Open fourth round.
World number one Iga Swiatek was working the night shift at Hard Rock stadium but also had trouble getting in gear before taming Czech 26th seed Linda Noskova 6-7(7) 6-4 6-4 to keep her bid for a second "Sunshine Double" - back-to-back wins at Indian Wells and Miami Open - on track.
While Swiatek was not at her best, the effort was enough to improve her season record to 22-2 and set up a meeting with 14th seed Ekaterina Alexandrova in the round of 16.
"Sometimes we have matches like that and we need to figure out how to close them anyway," Swiatek told reporters. "For sure it wasn't easy.
"There were just many ups and downs. I'm happy that after the first set I had a better idea on what to do, and I just tried to do that in important moments."
Gauff sleepwalked through much of her opening set in the first match on Hard Rock Stadium court, but when the alarm went off the US Open champion swept 10 straight games to stun the French lucky loser.
With Gauff pouring on the pressure, Dodin began to crumble, piling up nine double faults and 26 unforced errors compared to just seven by her 20-year-old opponent.
"She's a big hitter. She likes the game on her terms," Gauff told reporters. "I was trying my best to get deep in the court and just weather the storm.
"Overall I feel good so far.
"I'm trying to improve with each match. Definitely playing a little bit better than I was last week in Indian Wells."
With the win, Gauff matched her best Miami result and will await the winner between Caroline Garcia and Naomi Osaka for a place in the quarter-finals.
After a disappointing day for the American men on Saturday when three of the top four seeds exited, the U.S. women picked up the flag with fifth seed Jessica Pegula and 20th seed Emma Navarro also advancing.
Pegula, who has reached the Miami Open semi-finals for the last two years, took another step towards another appearance in the last four with a 7-5 6-4 win over Canadian Leylah Fernandez.
Navarro, coming off a quarter-final run last week at Indian Wells where she beat world number two Aryna Sabalenka and 17th ranked Elina Svitolina, continued her superb form in Miami with a 6-2 3-6 6-0 third round win over Italian 12th seed Jasmine Paolini.
In other action, 23rd seeded Frenchwoman Caroline Garcia came out on top 7-6(4) 7-5 in a third round slugfest with Japan's Osaka that featured a total of 28 aces.
Helped by 16 aces, Garcia has now won two matches at a tournament for the first time since the China Open last October and will next meet another big-hitter third seed Coco Gauff for a place in the quarter-finals.